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  1 / 2709 MEDLINE  
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[PMID]:28453779
[Au] Autor:Borges DA; Molina SMG; Pinto MC; Galati EAB; Cesario M; Ortiz DGS
[Ad] Endereço:Department of Genetics, Luiz de Queiroz College of Agriculture (ESALQ) - University of São Paulo (USP), Piracicaba, São Paulo, Brazil.
[Ti] Título:First Record of Lutzomyia (Lutzomyia) longipalpis (Diptera: Psychodidae: Phlebotominae) on the Trinational Frontier (Brazil-Peru-Bolivia) of South-Western Amazonia.
[So] Source:J Med Entomol;54(5):1425-1429, 2017 Sep 01.
[Is] ISSN:1938-2928
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In South America, the main sand fly species involved in the transmission of Leishmania infantum chagasi (Cunha & Chagas, 1937), etiological agent of the visceral leishmaniasis (VL), is Lutzomyia longipalpis (Lutz & Neiva, 1912). The species has been recorded in Colombia, Venezuela, Bolivia, Argentina, Paraguay, Uruguay, and Brazil, where it is recorded in 24 of the 27 Brazilian states, except Acre, Amazonas, and Santa Catarina. Collections were carried out for one year (April 2013 to March 2014) using modified CDC light traps in different environments in Assis Brasil municipality, state of Acre. Two males of Lu. longipalpis were found in peridomiciliary location in a peri-urban area. This is the first record of the species in Acre. This finding may be considered by the health agencies located in the trinational frontier, and new collections are needed to evaluate the real distribution of the species.
[Mh] Termos MeSH primário: Distribuição Animal
Insetos Vetores/fisiologia
Psychodidae/fisiologia
[Mh] Termos MeSH secundário: Animais
Brasil
Leishmania infantum/fisiologia
Leishmaniose Visceral/transmissão
Masculino
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1709
[Cu] Atualização por classe:180308
[Lr] Data última revisão:
180308
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170429
[St] Status:MEDLINE
[do] DOI:10.1093/jme/tjx086


  2 / 2709 MEDLINE  
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[PMID]:29324232
[Au] Autor:Aksoy S
[Ad] Endereço:Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA. Electronic address: serap.aksoy@yale.edu.
[Ti] Título:Insect Gut Microbiota: Accessories to the Bite.
[So] Source:Cell Host Microbe;23(1):8-9, 2018 01 10.
[Is] ISSN:1934-6069
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The Leishmania parasite is transmitted via the bite of a sand fly. In this issue of Cell Host & Microbe, Dey et al. (2018) report that sand fly gut microbiota are also transferred to the bite site, promoting neutrophil recruitment and parasite dissemination to distal organs.
[Mh] Termos MeSH primário: Microbioma Gastrointestinal
Psychodidae/parasitologia
[Mh] Termos MeSH secundário: Animais
Seres Humanos
Insetos Vetores/parasitologia
Leishmania
[Pt] Tipo de publicação:JOURNAL ARTICLE; COMMENT
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180112
[St] Status:MEDLINE


  3 / 2709 MEDLINE  
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[PMID]:29236932
[Au] Autor:Ortigão-Farias JR; Di-Blasi T; Telleria EL; Andorinho AC; Lemos-Silva T; Ramalho-Ortigão M; Tempone AJ; Traub-Csekö YM
[Ad] Endereço:Laboratório de Biologia Molecular de Parasitos e Vetores, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz-Fiocruz, Rio de Janeiro, RJ, Brasil.
[Ti] Título:Alternative splicing originates different domain structure organization of Lutzomyia longipalpis chitinases.
[So] Source:Mem Inst Oswaldo Cruz;113(2):96-101, 2018 Feb.
[Is] ISSN:1678-8060
[Cp] País de publicação:Brazil
[La] Idioma:eng
[Ab] Resumo:BACKGROUND The insect chitinase gene family is composed by more than 10 paralogs, which can codify proteins with different domain structures. In Lutzomyia longipalpis, the main vector of visceral leishmaniasis in Brazil, a chitinase cDNA from adult female insects was previously characterized. The predicted protein contains one catalytic domain and one chitin-binding domain (CBD). The expression of this gene coincided with the end of blood digestion indicating a putative role in peritrophic matrix degradation. OBJECTIVES To determine the occurrence of alternative splicing in chitinases of L. longipalpis. METHODS We sequenced the LlChit1 gene from a genomic clone and the three spliced forms obtained by reverse transcription polymerase chain reaction (RT-PCR) using larvae cDNA. FINDINGS We showed that LlChit1 from L. longipalpis immature forms undergoes alternative splicing. The spliced form corresponding to the adult cDNA was named LlChit1A and the two larvae specific transcripts were named LlChit1B and LlChit1C. The B and C forms possess stop codons interrupting the translation of the CBD. The A form is present in adult females post blood meal, L4 larvae and pre-pupae, while the other two forms are present only in L4 larvae and disappear just before pupation. Two bands of the expected size were identified by Western blot only in L4 larvae. MAIN CONCLUSIONS We show for the first time alternative splicing generating chitinases with different domain structures increasing our understanding on the finely regulated digestion physiology and shedding light on a potential target for controlling L. longipalpis larval development.
[Mh] Termos MeSH primário: Processamento Alternativo/genética
Quitinases/genética
Sistema Digestório/enzimologia
Psychodidae/enzimologia
[Mh] Termos MeSH secundário: Animais
Quitinases/fisiologia
Feminino
Filogenia
Psychodidae/fisiologia
Reação em Cadeia da Polimerase Via Transcriptase Reversa
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
EC 3.2.1.14 (Chitinases)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180215
[Lr] Data última revisão:
180215
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171214
[St] Status:MEDLINE


  4 / 2709 MEDLINE  
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[PMID]:29194438
[Au] Autor:González MA; Bandi KK; Bell MJ; Brazil RP; Dilger E; Guerrero A; Courtenay O; Hamilton JGC
[Ad] Endereço:Division of Biomedical and Life Sciences, Faculty of Health and Medicine, Lancaster University, Lancashire, United Kingdom.
[Ti] Título:A temporal comparison of sex-aggregation pheromone gland content and dynamics of release in three members of the Lutzomyia longipalpis (Diptera: Psychodidae) species complex.
[So] Source:PLoS Negl Trop Dis;11(12):e0006071, 2017 12.
[Is] ISSN:1935-2735
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Lutzomyia longipalpis is the South American vector of Leishmania infantum, the etiologic agent of visceral leishmaniasis (VL). Male L. longipalpis produce a sex-aggregation pheromone that is critical in mating, yet very little is known about its accumulation over time or factors involved in release. This laboratory study aimed to compare accumulation of pheromone over time and determine factors that might influence release in three members of the L. longipalpis species complex. METHODOLOGY/PRINCIPAL FINDINGS: We investigated male sex-aggregation pheromone gland content at different ages and the release rate of pheromone in the presence or absence of females under different light conditions by gas chromatography-mass spectrometry (GC-MS). Pheromone gland content was determined by extraction of whole males and pheromone release rate was determined by collection of headspace volatiles. Pheromone gland content appeared age-related and pheromone began to accumulate between 6 to 12 h post eclosion and gradually increased until males were 7-9 days old. The greatest amount was detected in 9-day old Campo Grande males ((S)-9-methylgermacrene-B; X ± SE: 203.5 ± 57.4 ng/male) followed by Sobral 2S males (diterpene; 199.9 ± 34.3) and Jacobina males ((1S,3S,7R)-3-methyl-α-himachalene; 128.8 ± 30.3) at 7 days old. Pheromone release was not continuous over time. During a 4-hour period, the greatest quantities of pheromone were released during the first hour, when wing beating activity was most intense. It was then substantially diminished for the remainder of the time. During a 24 h period, 4-5 day old male sand flies released approximately 63 ± 11% of the pheromone content of their glands, depending on the chemotype. The presence of females significantly increased pheromone release rate. The light regime under which the sand flies were held had little influence on pheromone release except on Sobral 2S chemotype. CONCLUSIONS/SIGNIFICANCE: Accumulation of pheromone appears to occur at different rates in the different chemotypes examined and results in differing amounts being present in glands over time. Release of accumulated pheromone is not passive, but depends on biotic (presence of females) and abiotic (light) circumstances. There are marked differences in content and release between the members of the complex suggesting important behavioural, biosynthetic and ecological differences between them.
[Mh] Termos MeSH primário: Insetos Vetores/fisiologia
Leishmania infantum/fisiologia
Leishmaniose Visceral/transmissão
Psychodidae/fisiologia
Atrativos Sexuais/metabolismo
[Mh] Termos MeSH secundário: Animais
Comportamento Animal
Diterpenos/metabolismo
Glândulas Exócrinas/metabolismo
Feminino
Cromatografia Gasosa-Espectrometria de Massas
Insetos Vetores/efeitos da radiação
Masculino
Psychodidae/efeitos da radiação
Reprodução
Sesquiterpenos/metabolismo
Sesquiterpenos de Germacrano/metabolismo
Atrativos Sexuais/análise
Atrativos Sexuais/química
Atrativos Sexuais/efeitos da radiação
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (9-methylgermacrene-B); 0 (Diterpenes); 0 (Sesquiterpenes); 0 (Sesquiterpenes, Germacrane); 0 (Sex Attractants); 0 (himachalene)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180212
[Lr] Data última revisão:
180212
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171202
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pntd.0006071


  5 / 2709 MEDLINE  
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[PMID]:29320544
[Au] Autor:González C; León C; Paz A; López M; Molina G; Toro D; Ortiz M; Cordovez JM; Atencia MC; Aguilera G; Tovar C
[Ad] Endereço:Centro de Investigaciones en Microbiología y Parasitología Tropical, CIMPAT, Departamento de Ciencias Biológicas, Universidad de los Andes, Bogotá, Colombia.
[Ti] Título:Diversity patterns, Leishmania DNA detection, and bloodmeal identification of Phlebotominae sand flies in villages in northern Colombia.
[So] Source:PLoS One;13(1):e0190686, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Leishmaniases are neglected tropical diseases exhibiting complex transmission cycles due to the number of parasite species circulating, sand fly species acting as vectors and infected mammals, including humans, which are defined in the New World as accidental hosts. However, current transmission scenarios are changing, and the disease is no longer exclusively related to forested areas but urban transmission foci occur, involving some species of domestic animals as suspected reservoirs. The aim of this study was to determine the transmission cycles in urban environments by evaluating sand fly diversity, detection of Leishmania DNA, and bloodmeal sources through intra and peridomestic collections. The study was carried out in Colombia, in 13 municipalities of Cordoba department, implementing a methodology that could be further used for the evaluation of vector-borne diseases in villages or towns. Our sampling design included 24 houses randomly selected in each of 15 villages distributed in 13 municipalities, which were sampled in two seasons in 2015 and 2016. Sand flies were collected using CDC light traps placed in intra and peridomestic habitats. In addition to the morphological identification, molecular identification through DNA barcodes was also performed. A total of 19,743 sand flies were collected and 13,848 of them (10,268 females and 3,580 males) were used in molecular procedures. Circulation of two known parasite species-Leishmania infantum and Leishmania panamensis was confirmed. Blood source analyses showed that sand flies fed on humans, particularly in the case of the known L. infantum vector, P. evansi; further analyses are advised to evaluate the reservoirs involved in parasite transmission. Our sampling design allowed us to evaluate potential transmission cycles on a department scale, by defining suspected vector species, parasite species present in different municipalities and feeding habits.
[Mh] Termos MeSH primário: DNA de Protozoário/genética
Comportamento Alimentar
Variação Genética
Insetos Vetores/parasitologia
Leishmania/genética
Psychodidae/parasitologia
[Mh] Termos MeSH secundário: Animais
Colômbia
Psychodidae/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Protozoan)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180210
[Lr] Data última revisão:
180210
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180111
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0190686


  6 / 2709 MEDLINE  
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[PMID]:29281639
[Au] Autor:Alkan C; Moin Vaziri V; Ayhan N; Badakhshan M; Bichaud L; Rahbarian N; Javadian EA; Alten B; de Lamballerie X; Charrel RN
[Ad] Endereço:UMR "Unité des Virus Emergents" (UVE Aix-Marseille Univ-IRD 190-Inserm 1207-EHESP), Marseille, France.
[Ti] Título:Isolation and sequencing of Dashli virus, a novel Sicilian-like virus in sandflies from Iran; genetic and phylogenetic evidence for the creation of one novel species within the Phlebovirus genus in the Phenuiviridae family.
[So] Source:PLoS Negl Trop Dis;11(12):e0005978, 2017 12.
[Is] ISSN:1935-2735
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Phlebotomine sandflies are vectors of phleboviruses that cause sandfly fever or meningitis with significant implications for public health. Although several strains of these viruses had been isolated in Iran in the late 1970's, there was no recent data about the present situation at the outset of this study. Entomological investigations performed in 2009 and 2011 in Iran collected 4,770 sandflies from 10 different regions. Based on morphological identification, they were sorted into 315 pools according to species, sex, trapping station and date of capture. A phlebovirus, provisionally named Dashli virus (DASHV), was isolated from one pool of Sergentomyia spp, and subsequently DASHV RNA was detected in a second pool of Phlebotomus papatasi. Genetic and phylogenetic analyses based on complete coding genomic sequences indicated that (i) DASHV is most closely related to the Iranian isolates of Sandfly fever Sicilian virus [SFSV], (ii) there is a common ancestor to DASHV, Sandfly fever Sicilian- (SFS) and SFS-like viruses isolated in Italy, India, Turkey, and Cyprus (lineage I), (iii) DASHV is more distantly related with Corfou and Toros viruses (lineage II) although common ancestry is supported with 100% bootstrap, (iii) lineage I can be subdivided into sublineage Ia including all SFSV, SFCV and SFTV except those isolated in Iran which forms sublineage Ib (DASHV). Accordingly, we suggest to approve Sandfly fever Sicilian virus species consisting of the all aforementioned viruses. Owing that most of these viruses have been identified in human patients with febrile illness, DASHV should be considered as a potential human pathogen in Iran.
[Mh] Termos MeSH primário: Genoma Viral/genética
Phlebovirus
Psychodidae/virologia
RNA Viral/genética
[Mh] Termos MeSH secundário: Animais
Sequência de Bases
Feminino
Seres Humanos
Insetos Vetores/virologia
Irã (Geográfico)
Masculino
Febre por Flebótomos/transmissão
Febre por Flebótomos/virologia
Phlebovirus/classificação
Phlebovirus/genética
Phlebovirus/isolamento & purificação
Filogenia
Análise de Sequência de RNA
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (RNA, Viral)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180130
[Lr] Data última revisão:
180130
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171228
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pntd.0005978


  7 / 2709 MEDLINE  
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[PMID]:29216181
[Au] Autor:Zhang B; Wang L; Liu J; Xu L; Song L; Wu X; Sun X; Wu Z
[Ad] Endereço:Department of Parasitology of Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China.
[Ti] Título:Case report: A rare case of urinary myiasis induced by the fourth instar larvae of Telmatoscopus albipunctatus.
[So] Source:PLoS Negl Trop Dis;11(12):e0006016, 2017 Dec.
[Is] ISSN:1935-2735
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Telmatoscopus albipunctatus, a cosmopolitan fly, is widely distributed throughout moist environments. It is one of the most medically important insects (especially in urban environments) that may potentially cause myiasis. Urinary myiasis and other sites of infestation, including the intestine, nasal passages, lung, and derma, have been reported. This is the first case report of a Chinese middlescent woman infected with T. albipunctatus in Guangzhou, China. In the present report, a 50-year-old woman came to The Third Affiliated Hospital of Southern Medical University, Guangzhou, China, because larvae were found when urinating in the morning; this had occurred every two days within the past two months. She complained of frequent micturition and urgency. Urine tests indicated that all indexes were normal except for slight urinary tract infection. Subsequently, the larvae were sent to the diagnostic section for parasitic infection in the Department of Parasitology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China. The stereoscopic microscope and transmission electron microscope were used for morphological observation. On this basis, the cytochrome oxidase subunit 1 (COX1) gene was specifically amplified by PCR. Sequence analysis of the PCR product and phylogenetic analysis were used to identify the species. Morphological analysis combined with molecular biology methods indicated that the insect was the fourth instar larvae of T. albipunctatus. Our results show that this was a case of a 50-year-old woman infected with T. albipunctatus larvae in her urinary tract, and the findings suggest that clinicians should be vigilant for this infection.
[Mh] Termos MeSH primário: Miíase/diagnóstico
Psychodidae
Infecções Urinárias/parasitologia
[Mh] Termos MeSH secundário: Animais
China
Feminino
Seres Humanos
Larva
Meia-Idade
Miíase/parasitologia
Filogenia
[Pt] Tipo de publicação:CASE REPORTS; JOURNAL ARTICLE
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171220
[Lr] Data última revisão:
171220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171208
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pntd.0006016


  8 / 2709 MEDLINE  
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[PMID]:29176865
[Au] Autor:Cecílio P; Pérez-Cabezas B; Fernández L; Moreno J; Carrillo E; Requena JM; Fichera E; Reed SG; Coler RN; Kamhawi S; Oliveira F; Valenzuela JG; Gradoni L; Glueck R; Gupta G; Cordeiro-da-Silva A
[Ad] Endereço:Parasite Disease group, Instituto de Investigação e Inovação em Saúde (i3S), Universidade do Porto, Porto, Portugal.
[Ti] Título:Pre-clinical antigenicity studies of an innovative multivalent vaccine for human visceral leishmaniasis.
[So] Source:PLoS Negl Trop Dis;11(11):e0005951, 2017 Nov.
[Is] ISSN:1935-2735
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The notion that previous infection by Leishmania spp. in endemic areas leads to robust anti-Leishmania immunity, supports vaccination as a potentially effective approach to prevent disease development. Nevertheless, to date there is no vaccine available for human leishmaniasis. We optimized and assessed in vivo the safety and immunogenicity of an innovative vaccine candidate against human visceral leishmaniasis (VL), consisting of Virus-Like Particles (VLP) loaded with three different recombinant proteins (LJL143 from Lutzomyia longipalpis saliva as the vector-derived (VD) component, and KMP11 and LeishF3+, as parasite-derived (PD) antigens) and adjuvanted with GLA-SE, a TLR4 agonist. No apparent adverse reactions were observed during the experimental time-frame, which together with the normal hematological parameters detected seems to point to the safety of the formulation. Furthermore, measurements of antigen-specific cellular and humoral responses, generally higher in immunized versus control groups, confirmed the immunogenicity of the vaccine formulation. Interestingly, the immune responses against the VD protein were reproducibly more robust than those elicited against leishmanial antigens, and were apparently not caused by immunodominance of the VD antigen. Remarkably, priming with the VD protein alone and boosting with the complete vaccine candidate contributed towards an increase of the immune responses to the PD antigens, assessed in the form of increased ex vivo CD4+ and CD8+ T cell proliferation against both the PD antigens and total Leishmania antigen (TLA). Overall, our immunogenicity data indicate that this innovative vaccine formulation represents a promising anti-Leishmania vaccine whose efficacy deserves to be tested in the context of the "natural infection".
[Mh] Termos MeSH primário: Anticorpos Antiprotozoários/sangue
Antígenos de Protozoários/imunologia
Imunogenicidade da Vacina
Vacinas contra Leishmaniose/imunologia
Leishmaniose Visceral/prevenção & controle
Saliva/imunologia
[Mh] Termos MeSH secundário: Adjuvantes Imunológicos/administração & dosagem
Animais
Seres Humanos
Imunidade Celular
Imunidade Humoral
Leishmania donovani
Leishmaniose Visceral/imunologia
Ativação Linfocitária
Masculino
Camundongos
Camundongos Endogâmicos BALB C
Psychodidae/imunologia
Psychodidae/parasitologia
Proteínas Recombinantes/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Adjuvants, Immunologic); 0 (Antibodies, Protozoan); 0 (Antigens, Protozoan); 0 (Leishmaniasis Vaccines); 0 (Recombinant Proteins)
[Em] Mês de entrada:1712
[Cu] Atualização por classe:171219
[Lr] Data última revisão:
171219
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171128
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pntd.0005951


  9 / 2709 MEDLINE  
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[PMID]:29049371
[Au] Autor:Courtenay O; Peters NC; Rogers ME; Bern C
[Ad] Endereço:School of Life Sciences, University of Warwick, Coventry, United Kingdom.
[Ti] Título:Combining epidemiology with basic biology of sand flies, parasites, and hosts to inform leishmaniasis transmission dynamics and control.
[So] Source:PLoS Pathog;13(10):e1006571, 2017 Oct.
[Is] ISSN:1553-7374
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Quantitation of the nonlinear heterogeneities in Leishmania parasites, sand fly vectors, and mammalian host relationships provides insights to better understand leishmanial transmission epidemiology towards improving its control. The parasite manipulates the sand fly via production of promastigote secretory gel (PSG), leading to the "blocked sand fly" phenotype, persistent feeding attempts, and feeding on multiple hosts. PSG is injected into the mammalian host with the parasite and promotes the establishment of infection. Animal models demonstrate that sand flies with the highest parasite loads and percent metacyclic promastigotes transmit more parasites with greater frequency, resulting in higher load infections that are more likely to be both symptomatic and efficient reservoirs. The existence of mammalian and sand fly "super-spreaders" provides a biological basis for the spatial and temporal clustering of clinical leishmanial disease. Sand fly blood-feeding behavior will determine the efficacies of indoor residual spraying, topical insecticides, and bed nets. Interventions need to have sufficient coverage to include transmission hot spots, especially in the absence of field tools to assess infectiousness. Interventions that reduce sand fly densities in the absence of elimination could have negative consequences, for example, by interfering with partial immunity conferred by exposure to sand fly saliva. A deeper understanding of both sand fly and host biology and behavior is essential to ensuring effectiveness of vector interventions.
[Mh] Termos MeSH primário: Leishmania/parasitologia
Leishmaniose/epidemiologia
Leishmaniose/transmissão
Parasitos/parasitologia
Psychodidae/parasitologia
[Mh] Termos MeSH secundário: Animais
Interações Hospedeiro-Patógeno/imunologia
Seres Humanos
Insetos Vetores/parasitologia
Leishmaniose/parasitologia
Parasitos/patogenicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE; REVIEW
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171020
[St] Status:MEDLINE
[do] DOI:10.1371/journal.ppat.1006571


  10 / 2709 MEDLINE  
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[PMID]:28991904
[Au] Autor:Kamiya T; Greischar MA; Mideo N
[Ad] Endereço:Department of Ecology & Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada.
[Ti] Título:Epidemiological consequences of immune sensitisation by pre-exposure to vector saliva.
[So] Source:PLoS Negl Trop Dis;11(10):e0005956, 2017 Oct.
[Is] ISSN:1935-2735
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Blood-feeding arthropods-like mosquitoes, sand flies, and ticks-transmit many diseases that impose serious public health and economic burdens. When a blood-feeding arthropod bites a mammal, it injects saliva containing immunogenic compounds that facilitate feeding. Evidence from Leishmania, Plasmodium and arboviral infections suggests that the immune responses elicited by pre-exposure to arthropod saliva can alter disease progression if the host later becomes infected. Such pre-sensitisation of host immunity has been reported to both exacerbate and limit infection symptoms, depending on the system in question, with potential implications for recovery. To explore if and how immune pre-sensitisation alters the effects of vector control, we develop a general model of vector-borne disease. We show that the abundance of pre-sensitised infected hosts should increase when control efforts moderately increase vector mortality rates. If immune pre-sensitisation leads to more rapid clearance of infection, increasing vector mortality rates may achieve greater than expected disease control. However, when immune pre-sensitisation prolongs the duration of infection, e.g., through mildly symptomatic cases for which treatment is unlikely to be sought, vector control can actually increase the total number of infected hosts. The rising infections may go unnoticed unless active surveillance methods are used to detect such sub-clinical individuals, who could provide long-lasting reservoirs for transmission and suffer long-term health consequences of those sub-clinical infections. Sensitivity analysis suggests that these negative consequences could be mitigated through integrated vector management. While the effect of saliva pre-exposure on acute symptoms is well-studied for leishmaniasis, the immunological and clinical consequences are largely uncharted for other vector-parasite-host combinations. We find a large range of plausible epidemiological outcomes, positive and negative for public health, underscoring the need to quantify how immune pre-sensitisation modulates recovery and transmission rates in vector-borne diseases.
[Mh] Termos MeSH primário: Vetores Artrópodes/imunologia
Modelos Biológicos
Saliva/imunologia
[Mh] Termos MeSH secundário: Animais
Culicidae/imunologia
Interações Hospedeiro-Parasita/imunologia
Seres Humanos
Tolerância Imunológica
Mordeduras e Picadas de Insetos/imunologia
Psychodidae/imunologia
Carrapatos/imunologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171109
[Lr] Data última revisão:
171109
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171010
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pntd.0005956



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